title: Nucleophilic halogenations of diazo compounds, a complementary principle for the synthesis of halodiazo compounds: experimental and theoretical studies.
abstract: Three new protocols for the nucleophilic halogenations of diazoesters, diazophosphonates, and diazopiperidinylamides as complementary methods to our previously reported electrophilic halogenations are presented for the first time. On the basis of hypervalent α-aryliodonio diazo triflate salts 1A, 2A, and 3A, the corresponding halodiazo compounds are generated via nucleophilic halogenations with tetrabutylammonium halides or potassium halides. The products from subsequent catalytic intermolecular cyclopropanations of the halodiazoesters and halodiazophosphonates and thermal intramolecular C-H insertion of the brominated diazopiperidinylamide are obtained in moderate to good yields after two steps. DFT calculations are presented for the diazoesters to give insight into the mechanism and transition states of the nucleophilic substitutions with the neutral nucleophiles dimethyl sulfide and triethylamine and the bromination with Br(-).
authors.affiliation: Department of Chemistry, University of Oslo, Sem Sælands vei 26, N-0315 Oslo, Norway.
authors.forename: Christian
authors.initials: C
authors.lastname: Schnaars
authors.forename: Martin
authors.initials: M
authors.lastname: Hennum
authors.forename: Tore
authors.initials: T
authors.lastname: Bonge-Hansen
mesh_terms: D003979:Diazonium Compounds / Q000737:chemistry*; D006846:Hydrocarbons, Halogenated / Q000138:chemical synthesis* / Q000737:chemistry; D015394:Molecular Structure; D011789:Quantum Theory
chemical_list: D003979:Diazonium Compounds; D006846:Hydrocarbons, Halogenated